[lld] [lld][WebAssembly] Preserve LTO stub deps for bitcode symbols (PR #173235)

[Sam Clegg via llvm-commits]

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@@ -1,6 +1,10 @@
 ## The function `bar` is declared in stub.so and depends on `foo` which is
 ## defined in an LTO object.  We also test the case where the LTO object is
 ## with an archive file.
+## The function `quux` is declared in stub.so and depends on `bar` which is
+## defined in an LTO object as well. In this case, `bar` is DCE'd and becomes
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sbc100 wrote:

It looks like baz is both defined in `foo.ll` and declared in `stub.so` to be importable.

https://github.com/llvm/llvm-project/pull/173235